BRAKE CONTROL APPARATUS AND BRAKE CONTROL METHOD

• US 20090326775A1
• Filed: 06/18/2009
• Published: 12/31/2009
• Est. Priority Date: 06/25/2008
• Status: Active Grant

• Current Assignee: Hitachi, Ltd.
• Original Assignee: Hitachi, Ltd.
• Inventors: NISHIDA, Shinichiro
• Granted Patent: US 8,352,142 B2
• Time in Patent Office: Days
• US Class Current: 701/70
• CPC Class Codes: B60T 7/22 initiated by contact of vehicle, e.g. bumper, with an external object, e.g. another vehicle , or by means of contactless obstacle detectors mounted on the vehicle
• CPC Class Codes: B60T 8/3225 Systems specially adapted for single-track vehicles, e.g. motorcycles B60T8/3235 takes precedence
• CPC Class Codes: B60T 8/4872 pump-back systems

Abstract

A brake control apparatus includes: a master cylinder; a wheel cylinder; a hydraulic pressure source; a control valve arranged to increase or reduce the pressure of the wheel cylinder; an outside gate valve arranged to connect or disconnect between the master cylinder and the wheel cylinder; a brake operation sensing section configured to sense a driver'"'"'s brake operation; and a control unit configured to control the hydraulic pressure source, the control valve, and the outside gate valve, to perform an automatic-brake pressure-increasing control to control the outside gate valve in a valve closing direction, to drive the hydraulic pressure source, and thereby to increase the pressure of the wheel cylinder in accordance with a vehicle condition, and to increase a driving quantity of the hydraulic pressure source when the brake operation is sensed during the automatic-brake pressure-increasing control.

Claims

1. A brake control apparatus comprising:

a master cylinder;

a wheel cylinder;

a hydraulic pressure source arranged to supply a hydraulic fluid sucked from the master cylinder to the wheel cylinder, and to increase a pressure of the wheel cylinder;

a control valve arranged to increase or reduce the pressure of the wheel cylinder;

an outside gate valve arranged to connect or disconnect between the master cylinder and the wheel cylinder;

a brake operation sensing section configured to sense a driver'"'"'s brake operation; and

a control unit configured

to control the hydraulic pressure source, the control valve, and the outside gate valve,

to perform an automatic-brake pressure-increasing control to control the outside gate valve in a valve closing direction, to drive the hydraulic pressure source, and thereby to increase the pressure of the wheel cylinder in accordance with a vehicle condition, and

to increase a driving quantity of the hydraulic pressure source when the brake operation is sensed during the automatic-brake pressure-increasing control.

2. The brake control apparatus as claimed in claim 1, wherein the control unit is configured to perform an automatic brake pressure-holding control to control the outside gate valve in the valve closing direction, to stop the hydraulic pressure source, and to hold the pressure of the wheel cylinder;

and the control unit is configured to drive the hydraulic pressure source when the brake operation is sensed during the automatic brake pressure-holding control, and to suck the hydraulic fluid from the master cylinder.

3. The brake control apparatus as claimed in claim 1, wherein the control unit is configured to perform an automatic brake pressure-reducing control to control the outside gate valve in a valve opening direction, to stop the hydraulic pressure source, and to reduce the pressure of the wheel cylinder;

and the control unit is configured to drive the hydraulic pressure source when the brake operation is sensed during the automatic brake pressure-reducing control, and to suck the hydraulic fluid from the master cylinder.

4. A brake control apparatus comprising:

a master cylinder;

a wheel cylinder;

a hydraulic pressure source arranged to supply a hydraulic fluid sucked from the master cylinder to the wheel cylinder, and to increase a pressure of the wheel cylinder;

a control valve arranged to increase or reduce the pressure of the wheel cylinder;

an outside gate valve arranged to connect or disconnect between the master cylinder and the wheel cylinder;

an inside gate valve provided between the master cylinder and a suction portion of the hydraulic pressure source;

a brake operation sensing section configured to sense a driver'"'"'s brake operation;

a control unit configured

to control the hydraulic pressure source, the control valve, the inside gate valve, and the outside gate valve,

to perform an automatic-brake pressure-increasing control to open the inside gate valve by a predetermined valve opening degree, to control a valve opening degree of the outside gate valve, to drive the hydraulic pressure source, and thereby to increase the pressure of the wheel cylinder in accordance with a vehicle condition, and

to increase the valve opening degree of the inside gate valve or a driving quantity of the hydraulic pressure source when the brake operation is sensed during the automatic-brake pressure-increasing control.

5. The brake control apparatus as claimed in claim 4, wherein the control unit is configured to increase the driving quantity of the hydraulic pressure source.

6. The brake control apparatus as claimed in claim 5, wherein the control unit is configured to decrease the driving quantity of the hydraulic pressure source with an elapsed time period from the detection of the brake operation when the brake operation is sensed.

7. The brake control apparatus as claimed in claim 5, wherein the control unit is configured to decrease the valve opening degree of the inside gate valve with an elapsed time period from the detection of the brake operation when the brake operation is sensed.

8. A brake control apparatus comprising:

a master cylinder;

a wheel cylinder;

a hydraulic pressure source arranged to supply a hydraulic fluid sucked from the master cylinder to the wheel cylinder, and to increase a pressure of the wheel cylinder;

a control valve arranged to increase or reduce the pressure of the wheel cylinder;

an outside gate valve arranged to connect or disconnect between the master cylinder and the wheel cylinder;

an inside gate valve provided between the master cylinder and a suction portion of the hydraulic pressure source;

a brake operation sensing section configured to sense a driver'"'"'s brake operation;

a control unit configured

to control the hydraulic pressure source, the control valve, the inside gate valve, and the outside gate valve,

to perform an automatic-brake pressure-holding control to close the inside gate valve and the outside gate valve, to stop the hydraulic pressure source, and to hold the pressure of the wheel cylinder in accordance with a vehicle condition, and

to open the inside gate valve, to drive the hydraulic pressure source, and thereby to suck the hydraulic fluid in the master cylinder when the brake operation is sensed during the automatic-brake pressure-holding control.

9. The brake control apparatus as claimed in claim 8, wherein the control unit is configured to increase the pressure of the wheel cylinder by the hydraulic fluid sucked from the master cylinder.

10. The brake control apparatus as claimed in claim 9, wherein the brake control apparatus further comprises a brake pedal, and a pedal operation quantity sensing section configured to sense an operation quantity of the brake pedal;

and the control unit is configured to calculate an increasing quantity of the pressure of the wheel cylinder based on the sensed operation quantity of the brake pedal.

11. The brake control apparatus as claimed in claim 9, wherein the brake control apparatus further comprises a brake pedal, and an operation time period sensing section configured to measure an operation time period from a start of the operation of the brake pedal;

and the control unit is configured to decrease the driving quantity of the hydraulic pressure source with the operation time period 8 sensed by the operation time period sensing section.

12. The brake control apparatus as claimed in claim 8, wherein the control unit is configured to decrease the driving quantity of the hydraulic pressure source with an elapsed time period when the brake operation is sensed.

13. The brake control apparatus as claimed in claim 8, wherein the control unit is configured to decrease the valve opening degree of the inside gate valve with an elapsed time period when the brake operation is sensed.

14. A brake control apparatus comprising:

a master cylinder;

a wheel cylinder;

a hydraulic pressure source arranged to supply a hydraulic fluid sucked from the master cylinder to the wheel cylinder, and to increase a pressure of the wheel cylinder;

a control valve arranged to increase or reduce the pressure of the wheel cylinder;

an outside gate valve arranged to connect or disconnect between the master cylinder and the wheel cylinder;

an inside gate valve provided between the master cylinder and a suction portion of the hydraulic pressure source;

a brake operation sensing section configured to sense a driver'"'"'s brake operation;

a control unit configured

to control the hydraulic pressure source, the control valve, the inside gate valve, and the outside gate valve,

to perform an automatic-brake pressure-reducing control to open the outside gate valve, to stop the hydraulic pressure source, and thereby to reduce the pressure of the wheel cylinder in accordance with a vehicle condition, and

to open the inside gate valve, to drive the hydraulic pressure source, and thereby to suck the hydraulic fluid in the master cylinder when the brake operation is sensed during the automatic-brake pressure-reducing control.

15. The brake control apparatus as claimed in claim 14, wherein the control unit is configured to increase the pressure of the wheel cylinder by the hydraulic fluid sucked from the master cylinder.

16. The brake control apparatus as claimed in claim 15, wherein the brake control apparatus further comprises a brake pedal, and a pedal operation quantity sensing section configured to sense an operation quantity of the brake pedal;

and the control unit is configured to calculate an increasing quantity of the pressure of the wheel cylinder based on the sensed operation quantity of the brake pedal.

17. The brake control apparatus as claimed in claim 15, wherein the brake control apparatus further comprises a brake pedal, and an operation time period sensing section configured to measure an operation time period from a start of the operation of the brake pedal;

and the control unit is configured to decrease the driving quantity of the hydraulic pressure source with the brake operation time period of the brake sensed by the operation time period sensing section.

18. The brake control apparatus as claimed in claim 14, wherein the control unit is configured to decrease the driving quantity of the hydraulic pressure source with an elapsed time period when the brake operation is sensed.

19. The brake control apparatus as claimed in claim 14, wherein the control unit is configured to decrease the valve opening degree of the inside gate valve with an elapsed time period when the brake operation is sensed.

20. A brake control method comprising:

performing an automatic brake control including;

a pressure increasing control to suck a hydraulic fluid from a master cylinder at least by a hydraulic pressure source, and to increase a pressure of a wheel cylinder by the hydraulic fluid from the master cylinder in accordance with a vehicle condition;

a pressure holding control to hold the increased pressure of the wheel cylinder; and

a pressure reducing control to reduce the pressure of the wheel cylinder;

sensing a driver'"'"'s further depression during the automatic brake control; and

flowing the hydraulic fluid in the master cylinder to the wheel cylinder when the further depression is sensed during the automatic brake control.

21. The brake control method as claimed in claim 20, wherein the control unit is configured to flow the hydraulic fluid in the master cylinder to the wheel cylinder by the hydraulic pressure source.